A remake of the comedy spin-off manga Koha-Ace GO: Teito Seihai Kitan.

The manga is an anthology story centering on the Crypters, the betrayer agents of Chaldea that are the center of the Fate/Grand Order smartphone game's "Lostbelt" story line.

Hana no Miyako is a Tsukihime and Melty Blood spin-off about Shiki Tohno's cousin, Miyako Arima.

Fate/Grand Order tie-in webcomic

Manga adaptation of Type-Moon's Mahou Tsukai no Hako project.

The original Fate/Type Redline. Yes. The serious Fate/Type Redline originated from a comedy Koha-Ace manga. Follow the adventures of Kohaku and Akiha (characters from Tsukihime) as they fight in the Imperial Capital Grail War with Okita Souji!

When Lord El-Melloi II, the later Waver Velvet, gets asked to claim his inheritance over Adra Castle, he travels there with his apprentice Gray to do so. But they are not the only ones called that way. The will of the previous owner states that the assembled contestants—including Luviagelita Edelfelt—must compete in a game of wits to win the castle.

The plot centers around a Grail War faultily copied from the Third Holy Grail War in Fuyuki. After the end of the third Grail War, an organization from the United States that has magi separate from the London-based Mage Association as members took data from Fuyuki's Grail War and planned their own ritual. After seventy years, they used the city Snowfield as the Sacred Land for their own Grail War. They were unable to successfully copy every aspect of the ritual, which lead to it acting only as an imitation that has lost the Saber class and allowed for the summoning of strange Servants due to the definition of a "hero" being blurred.

(Source: Type-Moon Wikia)

Being flung from the world of Fate/Extra Kishinami Hakuno finds himself in a very strange predicament. Caster Route.

A TYPE-MOON staff member artist Takenashi Eri has created many side stories to most of the group's projects; 'Tsukihime' & 'Kagetsu Tohya', 'MELTY BLOOD', 'Fate/stay night' -- you'll find your favorite characters in various hilarious situations that weren't covered by any of the original products.
from Baka-Upates Manga

Melty Blood (メルティブラッド, Meruti Buraddo?), is a visual novel and fighting game, co-developed by dōjin circles Type-Moon and French-Bread, originally released at Comiket on December 2002. It is shortened as simply Merubura (メルブラ?).

Based on Type-Moon's visual novel game, Tsukihime, it later spawned an arcade version, titled Act Cadenza, that was developed by Ecole Software and has also been ported to the PlayStation 2. Act Cadenza is the first Type-Moon title to receive a PlayStation 2 port.

A manga version by Takeru Kirishima has been serialized in Kadokawa Shoten's Comp Ace.

[from wikipedia]

A manga which helps you learn about Fate/Grand Order!(Source: MangaDex)

A Fate/stay Night spin-off focused on cooking.

The story follows Tohno Shiki, a teenage boy who, after a near-fatal accident in his childhood, gained the mysterious power to perceive lines covering everything around him. When he cuts along these lines, whatever it was immediately falls apart with a clean cut; in other words, killing it. He would have quickly gone insane from living in a world that could fall apart so easily, had it not been for a wandering self-proclaimed magician who gave him a pair of glasses that blocked his unnatural perception when worn.

Soon afterwards, he was disinherited from his family and sent to live with some relatives. For eight years he lived a normal life, hiding his special eyes, until one day he receives a letter inviting him to come back home. Shiki suddenly becomes caught up in strange and life-threatening series of events, ones that are somehow linked to his childhood accident and a forgotten past...

War of the Holy Grail—Pursuing the power of the "Holy Grail" which grants a miracle, this is a contest in which seven magi summon seven Heroic Spirits to compete for it. In that battle whose conclusion was postponed three times, now, the fourth war commenced again. Entrusting their dearest wish of victory, the magi joined the battleground called "Fuyuki," but amongst them, there was a man who was always alone, and could not find out the meaning behind his fights. His name was Kotomine Kirei. Not comprehending the guidance of fate, Kirei was lost, and had kept questioning. Why someone like his was given the Command Seals. However, the fate of his fights crossed Kirei's path with a nemesis by chance. That person is—Emiya Kiritsugu. A man who was sterner than anyone else, more merciless than anyone else, and who sought the miracle of the Holy Grail.

Merely recited in fragments in Fate/stay night, this is the Fourth War of the Holy Grail 10 years ago. The truth which unfolded behind the battle between Shirou's foster father, Rin's father, and the younger Kotomine Kirei, is finally revealed...

(Source: Baka-Tsuki)

The year is 2016 a.d. Some time ago, humanity had escaped the path to peril. This tale takes place after that period. This is the tale of a hero once again~

Manga adaptation of the scenario that Type-Moon co-founders Kinoko Nasu and Takashi Takeuchi, created for the Nintendo Wii visual novel 428: Fūsasareta Shibuya de.